After transmigrating to the Great Yan dynasty, Lu Bai just wants to lie flat and enjoy his retirement. He voluntarily surrenders command of two hundred thousand troops and takes a sinecure as a junior tutor in the Eastern Palace, where he can eat his fill and wait to die.
"Your Majesty, the Great General of Divine Strategy has handed over his military tally and requested a post in the Eastern Palace. He's playing mahjong with the Crown Prince right now!"
The Great Yan Emperor sighs in relief. "Granted. As long as he doesn't rebel, let him be."
A month later.
The Emperor asks, "Lord Lu, what statecraft did the Crown Prince study today?"
Lu Bai replies, "Your Majesty, I taught him mahjong. He just learned how to call a pung and cut in to claim a win."
The next day, the Crown Prince shouts in court, "Isolate the chief culprit and win over the lesser ones. That's the art of cutting in to claim a win!" He promptly crushes the all-powerful Grand Chancellor!
A great scholar of the Imperial Academy is argued into vomiting blood on the spot. "This is the 'cut-in-and-claim-a-win school of vertical and horizontal alliances,' taught by the Crown Prince's mentor!"
Two months later, the Crown Prince rolls out an enormous steel cannon and blows apart a mountain pass. "My mentor says this is called 'truth is only found within the range of the cannons'!"
Three months later, refugees revolt. The Crown Prince pulls out a deck of cards and shouts, "Overthrow the landlords and divide the land! Charge with me!"
Looking at the court full of civil and military officials kneeling in worship, Lu Bai is on the verge of tears. "System, stop messing with me! I really just taught him to slack off and play cards. How did he turn the whole world upside down?!"
Even more absurdly, the stunningly beautiful female warlord of Xiliang arrives with a hundred thousand cavalry to demand his hand in marriage. "Lu, my bride price is three iron mines. You and I are spending the night together, no excuses!"
Lu Bai throws his head back and cries out to the heavens: I just wanted to eat my fill and wait to die. How did I end up as the greatest imperial tutor in history?